Refrigerator



M. C. TERRY REFRIGERATOR Aug, 18, 1931,

Filed Oct. 30, 1928 2 Sheets-Sheet 1 INVENTOR Mazsoi'z 6'. Terry;

' ATfoNE M. C. TERRY Aug. 1, E31.

REFRIGERATOR Filed Oct. so, 1928 2 Shee ts-Sheet 2 u/ if w C m n 0 w mA'TRNE I Patented -Aug. 1s, 1931 UNITED STATES PATENT- OFFICE MATSON C.TERRY, MANSFIELD, OHIO, ASSIGNOR TO WESTINGHOUSE ELECTRIC &

MANUFACTURING COMPANY, A CORPORATION OF PENNSYLVANIA REFRIGERATORApplication filed October 30, 1928. Serial No. 316,068.

My invention relates to refrigerating machines and particularly torefrigerating machines of the compression type and of small capacity,such as are suitable for household use, and it has for an object toprovide apparatus of the character designated which shall operate withan extraordinary degree of efliciency, reliabilit and effectiveness.

It has for a furt er object to provide, in

1D compression refrigerating apparatus comprising essentially acompressor for translating and compressing refrigerant vapor, a motorfor driving the compressor, a condenser for liquefying the compressorrefrig erant vapor and an evaporator for absorbing heat from theelements to be cooled and, incidentally, vaporizing the liquefiedrefrigerant and an improved arran ement for cooling the condenser whichshall be especially applicable to refrigerating machines wherein themotor and the compressor are both totally enclosed in a fluid-tight orhermetically sealed casing.

It has for still another object to provide a fan, together with animproved means for driving the same, which fan shall be locatedexteriorly of the casing enclosing the compressor and the motor, butwhich shall be motivated by the latter without, in any way, affectingthe fluid-tight qualities for hermetically sealing the casing enclosingthe motor and the compressor.

These and other objects are effected by my invention, as will beapparent from the following description and claims taken in connectionwith the accompanying drawings, constituting parts of this application,in which:

Fig. 1 is a sectional view of a sealed-motor compressor unit embodyingmy invention;

Fig. 2 is an end view showing the condenser and the fan;

Fig. 3 is an enlarged sectional view of a portion of what is shown inFig. 1, showing the details of the fan drive;

Fig. 4 is a plan view of the toothed secondary rotor element;

Fig. 5 is a section taken on line V-V of Fig. 4;

d l31;ig. 6 is a plan view of a secondary rotor Fig. 7 is a section online VIIVII of Fig. 6;

Fig. 8 is an elevation and Fig. 9 a plan view of the lubricating pin;

Fig. 10 is an elevation and Fig. 11 is a plan view of the magneticportion of the primary rotor element;

Figs. 12 and 13 are an elevation and a plan view, respectively, of thenon-magnetic portion and pole pieces of the primary rotor element.

In many refrigerating machines heretofore constructed, a separatecompressor and a motor for driving the same have been provided with anexternal drive shaft for connecting the motor to the compressor. Suchrefrigcrating machines, however, require the provision of a stufiing boxor gland for the shaft connecting the motor to the compressor in orderto prevent the escape of refrigerant fluid from, or the infiltration ofair into, the compressor housing. The provision of such gland is,however, undesirable for the reason that it must be adjusted or attendedto frequently if it is to maintain a seal about the drive shaft whichshall be entirely fluid tight and unless it is so maintained, there isapt to be either a leakage of refrigerant fluid out of the system or aninfiltration of air into the system. As refrigerating machines of thehousehold type have a relatively small volumetric capacity, a slightamount of leakage of refrigerant or infiltration of air will interferematerially with the successful operation of the machine. Refrigeratingmachines of this character are generally referred to as of the opentype. 7

It has, therefore, been proposed to have the compressor and its drivingmotor located in a single, hermetically sealed casing, which may beadapted to contain refrigerant fluid. By means of such an arrangement,the requirement for a stufling box or gland for the drive shaftconnecting the motor to the compressor is entirely dispensed with,inasmuch as the entire operating mechanism may be confined within theinterior of the casing, whereby complete fluid-tightness of therefrigerating system is assured. Refrigerating machines of thischaracter are generally referred to as of the enclosed type.

With refrigerating machines of the open type, a fan is usually providedfor circulating cooling air over the condenser, which fan may be readilyconnected or coupled to the external drive'shaft connecting the motor tothe compressor. Then again, it may be em: bodied integrally with the flyWheel provided on the compressor. However, with refrigerating machinesof the enclosed type, the fan for circulatin cooling air over thecondenser must necessarily be located exteriorly of the casing whichencloses the motor and the compressor and, to drive this fan byconnecting or coupling the same mechanically to either the motor or thecompressor inside of the casing, would involve the provision of a fandrive shaft extending through the casing and, hence, the entire basicidea of providing a totally enclosed hermetically sealed system would bedefeated. It has, therefore, been proposed to provide a second orseparate 5 motor for driving the fan, which motor is located exteriorlyof the enclosing casing and directly coupled to the fan. Preferably, thearrangement is such that the separate motor-driven fan draws cooling airover the so condenser and discharges it over the casing enclosing themotor and compressor, so that the condenser, the motor and thecompressor are effectively cooled. -However, the latter arrangement isobjectionable in some respects motors,'together with starting andcontrol apparatus for each. Furthermore, a motor of very small capacityis suflicient for driving the fan andsuch motors, are relativelyinefiicient and relatively unreliable, as compared with the main motor,that is, the motor driving the compressor. In addition, the provision oftwo motors increases the manufacturing cost of the refrigeratingmachine.

Furthermore, if separate motors are provided for the condenser and thefan, and the fan motor fails to operate, inadequate condensation of thegaseous refrigerant will result, and dangerously high pressures will beproduced as long as the compressor continues to operate.

It has also been proposed, in enclosed refrigerating machines, todispense with the fan and to depend upon the natural radiation of theheat of condensation to the atmosphere. However, such a provisiongreatly increases the cost of condensation because of the necessity ofproviding an enlarged condenser surface, as compared with a condensercooled by a forced draft, even taking into consideration the cost of thefan and its driving means, and, in additionfinterferes with thecompactness of the refrigerating machinery. In other words, in order toobtain the same condenser efficiency, using the in that it involves theprovision of twonatural radiating "surface of the condenser only, it isnecessary to use an inordinately large amount of expensive condensermaterial, as compared with the amount of condensing surface necessarywhen forced air circulation is used.

I have, therefore, conceived the idea of providing, in enclosedrefrigerating machines, a fan for effecting a forced circulation of airoverthe condenser, and, preferably, in addition, over the casingenclosing the motor and the compressor, or, in the event that the casingis adapted to act as the condenser over the casing alone and of havingsuch fan driven inductively from the motor or compressor located insidethe enclosing casing. By means of such arrangement, only one motor isrequired and the hermetical sealing of the enclosing casing is not, inany way, affected or interfered with. Furthermore, such arrangementprovides a refrigerating machine-capable of operating with a higherdegree of efliciency than refrigerating machines of the type in which afan is dispensed with and with a higher degree of reliability and ahigher overall efficiency than refrigerating machines wherein a separatemotor is provided for driving the same, my experiments showing that aninductive driving arrangement for the fan consumes only onesixth toone-seventh of the electrical energy necessary for a separate fan motor.

Referring now to the drawings for a more detailed description of myinvention, I show a hermetically sealed casing 10 embodying a centralcylinder 11 provided with removable end cover plates secured thereto andretained in fluid-tight engagement therewith, by bolts 13. Disposedwithin the casing 10 is a refrigerant compressor 14 driven by a motor 115, the motor being operatively connected to the compressor by asuitable drive shaft 16. While, in the present embodiment, I have showna compressor of the reciprocating type directly coupled to the motor,nevertheless 110 it is understood that my invention is also applicableto any form of compressor having the moving parts thereof entirelyconfined within the enclosing casing. Furthermore, while I show a formof compressor 115 which is directly coupled to the motor, nevertheless,it is obvious that other forms of drive means may be provided withoutdeparting from the spirit or scope of the presentinvention.

The drive shaft 16 is provided with an extended portion 17 to which issecured, as by a nut 18, a primary rotor element 19. The

latter is composed of a central, non-magnetic of a metal which isrelatively non-magnetic and preferably a relatively highelectricalresistance characteristic. The cup-shaped member 27 issecured, in a fluid-tight manner, to one of the end cover plates 12 by areinforcing ring 28 and bolts 28'. In addition, the cup-shaped member 27may be further secured to the end cover plate by welding or brazing.

Disposed exteriorly of the cup-shaped member 27 and in proximaterelation thereto, is a secondary rotor element 30, which rotor element,as shown in Figs. 4 and 5, is essentially composed of a conductingmember 31 having teeth 32 extending in an axial direction and arrangedto retain a plurality of discs 33, each of which is preferably composedof material which is a relatively good electrical conductor. Provided onthe end plate 12 is an annular projection 34 for housing the secondaryrotor element 30.

Located and fixed in the central portion of the cup-shaped member 27 isa bearing pin 41 upon which the secondary rotor element is rotatablysupported, a bushing 42 being pressed into or fixedly retained in theaxis of the secondary rotor element 30 for effecting bearing engagementwith the retaining pin 41. The bearing pin 41 supports the secondaryrotor element 30 and provides the axis about which the latter rotates.

Secured to the outer face of the secondary rotor element 30 is acircular member 45 forming a lubricant reservoir 44, while, dlsposedbeyond the lubricant reservoir and in abutting relation therewith, is acooling fan 45. Both the cooling fan 45, and the circular member 43 areretained in abutting relation with the secondary rotor element 30 by aplurality of circumferentially spaced screws 46, preferably formed asillustrated. A gasket may be provided between the secondary rotorelement 30 and the ring member 28 to effect a lubricant seal. Acondenser element 47 is disposed adjacent to the fan 45 and in the pathof the air stream created thereby.

In the present embodiment, the fan preferably first draws air over thecondenser and then discharges it in the direction of the enclosedmotor-compressor unit, although it is .within the purview of myinvention to so arrange the fan that it first draws air over the motorcompressor unit and then discharges it over the condenser. However, Ihave found the former arrangement to be preferable, in that, in thisway, heat generated by the motor and compressor during operation, iseffectively dissipated after the cool air has passed through thecondenser.

The condenser 47 consists, essentially, of a spiral coil of tubing 48although it is obviout that other forms of condensers may be employedwithout departing from the spirit or scope of my invention. Thecondenser 47 receives refrigerant vapor from the enclosed motor andcompressor through a conduit 49 and discharges the liquefied refrigerantthrough an outlet 50 to the evaporator 61 through the conduit 62 andexpansion valve 63. Expanded refrigerant is returned to the compressor14 through a conduit 64. The condenser 47 may be supported, by means ofbrackets 51, from the bolts '13 of the casing. The conduit 64 leadsdirectly to a chamber 65 which communicates with the compressor intakeside. The conduit 47 which conveys the high-pressure gas to thecondenser is directly connected to the interior of the sealed casing, sothat the discharge pressure of the compressor prevails Within the casing10. The construction of the compressor is shown and described in thecopending application of Frank Conrad and Christian Aalborg, Serial No.204,401, filed July 8, 1927, for Refrigerator and assigned to the\Vestinghouse Electric & Manufacturing Company.

Fixed to the bearing pin 41 is a radiallyextending lubricating pin 52for conveying the lubricant from the periphery of the lubricantreservoir-to the bearing pin. As shown in Figs. 6 and 7, the lubricantpin 52 is provided with a radially-extending portion 53 and a curvedportion 54, the curved portion being offset axially with respect to theradial portion, as shown particularly in Fig. 8. The arrangement is suchthat, when the radial portion 53 of the pin is inserted in a diametralhole 55 in the bearing pin 41, the curved portion 54 engages or embracesan annular groove 55 in the bearing pin, this portion of the lubricantpin serving as a spring lock washer to retain the secondary rotorelement 30 in axial position on the bearing pin.

Provided in the bearing pin 41 and extending longitudinally thereto, isa lubricant passage-way 56 which communicates with the diametral hole 55for supplying lubricant to the bearing surface intervening between thebearing pin and the bushing 42 of the secondary rotor element. Suitableoil grooves 56 are provided in the bushing 42 for distributing thelubricant over the entire bearing surface. The grooves 56 are preferablyof helical form to efiect a flow of lubricant throughout the bearing andback to the reservoir 44, the lubricant escaping from the outer end. ofthe bearing and draining into the reservoir. Any lubricant which maytravel in the opposite axial direction, that is, towards the motor andthe compressor, is trapped by an annular groove '57 provided in thebushing 42 and returned, through a plurality of circumferentially-spacedholes 58, to the reservoir 44. If any lubricant escapes past saidtrapping means, it becomes deposited upon the inner radial face of thesecondary rotor element 30 upon which an annular ledge 59 is provided.The lubricant is moved by centrifugal force and impinged against thisledge from which it is carried, also by disposed,circumferentially-spaced holes,

such as 60. I

In the operation of my device, the motor is started by the operation ofmeans, such as a' thermostat (not shown), which is responsive to therefrigerator chamber temperature. The starting of the motor causes thecompressor 14, the shaft 16 and the primary rotor element 19 to rotate.The magnets 24 and pole pieces 25 supply fluxwhichpasses through thenon-magnetic cup-shaped member 27 to the teeth and the body of member31. As the primary and secondary rotor elements move relative to eachother, the flux cuts through the discs 33 carried by member 31, causinga current to flow similar to the armature current in a direct-currentmotor. This current, reacting with the field around it, causes thesecondary rotor element carrying the fan to rotate, thereby producing aforced draft of air to cool the condenser. There is a certain aniount oflag present between the primary and the secondary rotor element whichcauses the fan to rotate at a lower speed than the motor. This lag maybe regulated by the size of the air gap between the rotor elements andcup shaped member 27, so that the fan may be driven at considerably lessspeed than the motor and compressor, thereby reducing or eliminating thenoise caused by the fan and, at the same time, producing an effectivecooling of the condenser.

The term hermetically sealed casing, as

usedin this specification, is intended to include the broad meaninggenerally accepted in the refrigerating industry, that is, a casingwhich is substantially gas tight and which has no rotating shafts orother moving parts projecting through or beyond its walls. Likewise, theterm fan includes any movable means designed to circulate air.

While I have shown only a single form of my invention, it is apparentthat other forms may be provided, all coming within the scope of theappended claims.

I claim as my invention:

1. In a refrigerating apparatus, in combination, a hermetically sealedcasing, a motor and a compressor within the casing, an evaporator, acondenser, and a fan actuated by the motor for forcing air around thecondenser.

2. In a refrigerating apparatus, in combination, a hermetically sealedcasing, a motor and a compressor Within the casing, an evaporator, acondenser, and a fan inductively actuated by the motor for forcing airaround the condenser.

3. In a refrigerating apparatus, in combination, a hermetically sealedcasing, a compressor and a rotating driving element there- 1 forenclosed within the casing, an evaporator, a condenser, and a fanlocated exteriorly of the casing and actuated by the rotating drivingelement.

4. In a refrigerating apparatus, a hermetically-sealed casing, acompressor and driving means therefor located entirely within thecasing, an evaporator, a condenser, and a fan located outside the casingand actuated by the compressor-driving means.

5. Refrigerating apparatus comprising a heat-absorbing unit and aheat-dissipating unit, said heat-dissipating unit comprising ahermetically sealed casing containing a motor and a compressor and'a fanlocated exteriorly of the-casing and driven by the motor.

6. In a refrigerating apparatus, an evaporator, a condenser, ahermetically sealed casing containing a motor and compressor and meansfor dissipating heat evolved in the cas ing and condenser, said meanscomprisin air-circulating means outside the casing an driven by themotor.

7. In a refrigerating apparatus, in combination, a hermetically sealedcasing containing a refrigerant-circulating, unit including a motor, anevaporator, a condenser and a fan inductively driven from the motor forcooling the condenser.

8. In a refrigerating apparatus, an evaporator, a condenser, ahermetically sealed casing, a motor and a compressor within the easing,a fan located outside the casing, and a magnetic clutch actuated by themotor for driving the fan.

9. In a refrigerating apparatus, an evapo rator, a condenser, ahermetically sealed casing, a motor and a compressor within the casing,a fan located outside the casing, and a magnetic clutch actuated by themotor for driving the fan, the clutch having its driving part inside thecasing, and its driven part outside the casing.

10. In a refrigerating apparatus, in combination, an operativelyconnected compressor, condenser and evaporator, a motor for driving thecompressor, a hermetically sealed casing enclosing the motor and thenections, a hermetically sealed casin the compressor and a driving motortherefbr being disposed within the casing, a shaft connecting the motorand the compressor, a fan outside the casing, a shaft supporting saidfan, a magnet carried by one of said shafts, and an armature carried bythe other of said shafts, whereby the fan is rotated when the motor isoperated.

12. In a refrigerating apparatus, in combination an evaporator, acondenser and a compressor operatively interconnected, a motor having ashaft connected to the compressor, a fan having a shaft, a magnetcarried by one of the shafts, an armature carried by the other of theshafts adjacent to the magnet, and a hermetically sealed casingenclosing the motor and the com ressor, the casing having a wallinterposed etween the magnet and the armature.

13. In a refrigerating apparatus, in combination, an evaporator, acondenser and a compressor operatively interconnected, a motor having ashaft connected to the compressor, a fan having a shaft, a magnetcarried by one of the shafts, an armature carried by the other of theshafts adjacent to the magnet, and a hermetically sealed casingenclosing the motor and the compressor, the casing having a relativelynon-magnetic wall interposed between the magnet and the armature.

14. In a refrigerating apparatus, an evaporator, a condenser, ahermetically sealed casing, a compressor and driving means thereforlocated within the casing, a fan outside the casing for cooling thecondenser, and means actuated by the compressor-driving means fordriving the fan at a speed less than that of the driving means.

15. In a refrigerating apparatus, an evaporator, a condenser, ahermetically sealed casing, a motor and a compressor entlrely within thecasing for cooling the condenser, a fan located outside the casing, andmeans actuated by the motor for driving the fan at less than motorspeed.

16. In a refrigerating apparatus, in combination, an evaporator, acondenser, a hermetically sealed casing, a motor and a com-' pressorwithin the casing, the casing including a wall, a fan rotatablysupported by the wall, and means actuated by the motor for driving thefan.

17. In a refrigerating apparatus, in combination, an evaporator, acondenser, a hermetically sealed casing, a motor and a compressorentirely within the casin the casing having a cup shaped wall ofrelatively non-magnetic material, a primary. rotor element within thecasing, a secondary rotor element outside the casing and adjacent to thenon-magnetic wall, a fan driven by the secondary rotor element forcooling the condenser, and a projection on the casing extending aroundthe secondary rotor element.

18. In a refrigerating apparatus, a hermetically sealed casing, anevaporator, a con denser, a motor and a compressor within the casing,the casing having a relatively non magnetic wall, a fan for cooling, thecondenser located outside the casing and adjacent the wall, and meansresponsive to movement of the motor for actuating the fan.

19. In a refrigerating apparatus, in combination, a. condenser, anevaporator and a compressor operatively interconnected, a fan forcooling the condenser, a common means for driving both the compressorand the fan,

and means for hermetically sealing the compressor and at least a portionof said driving means.

'20. In a refrigerating apparatus, in combination, an evaporator, acondenser, a hermetically sealed casing, a compressor-and driving meanstherefor located within the casing, a fan located outside the casing andsupported thereby, and actuated by the compressor driving means.

21. Refrigerating apparatus comprising a heat-absorbing unit and aheat-dissipating unit, said heat-dissipating unit comprising a rotatingdriving element, a compressor driven thereby, a hermetically sealedcasing enclosing said driving element and compressor, and a fan mountedexternally of the casing and having a part adjacent thereto with an airgap between the casing and said part, characterized by the fact thatmeans are provided within the casing for producing a rotating magneticfield in the portion of the casing bounded by the air gap, the part ofthe fan apparatus adjacent to said air gap being of such nature as to berotated by said field.

In testimony whereof, I have hereunto subscribed my name this 13 day ofOct. 1928.

MATSON C. TERRY.

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